Laminated article and method of making the same



NOV; 24, 1936. J POLLARD 2,061,951

LAMINATED ARTICLE AND METHOD OF MAKING THE SAME Filed Feb. 5, 1935 'raieaaa Nov. 24, E936 rep s'rAres PAT LAMINATED ARTICLE AND METHOD OF MAKING THE SAIVIE Application February 5, 1935, Serial No.5,l51

1? Claims.

This invention relates to articles made from laminated materials and to their method of manufacture by which certain characteristics are imparted to the article, both with relation to 5 strength and durability and also to ornamental appearance. While the products of the method of this invention are not restricted to any particular use, one article in the production of which the method of this invention is of particular advantage is a shoe heel, and the invention will be further described with more particular reference to shoe heels and to the characteristics desirable in such heels.

When a heel is made of superposed laminations or lifts of leather, natural variations in the texture of the leather in the different lifts and within different portions of the same lift cause the exposed edges in the completed heel to take coloring material differently where this coloring 20 is not applied too heavily, thus producing in the finished heel pleasing variations of color shades between adjacent lifts and in different portions of the same lift. I'hese variations consist primarily of relatively darker and lighter bands of color of somewhat indefinite outline and of width usually less than the thickness of the lift. The same variations in leather structure which produce these desirable variations in color have the undesirable effect, however, of causing unequal ability of the lifts to resist stresses of use. This results in creeping of the softer lifts and the softer parts of individual lifts so that they project outwardly beyond their original positions after a time of use and destroy the smooth symmetrical appearance of the heel surface. Usually, due to the'expense of leather lifts of good quality, other materials have been substituted quite largely for leather, particularly intermediate the top and bottom faces of the heel, a -leather lift being commonly employed as the top lift at the tread end of the heel, and another being used for the concave heel seat next to the shoe. The intermediate lifts have been made commonly of sheeted interfelted fibrous material such as leatherboard, or for very cheap shoes, of a pressed paperboard. Lifts formed of wood have also been employed to a small extent.

Heels formed from leatherboard or other usual fibrous laminations take color evenly and are often so friable that they do not withstand service entirely satisfactorly and they are liable to check or separate or split due to the effects of moisture, and to creep. In order to produce color variations in the surfaces of heels formed from such material, it has been proposed to alternate lifts subjected to different color treatments, or to interpose layers of other material such'as sheet pyroxylin or the like between the lifts of fibrous material. Not only does this require care in assembling lifts to properly relate successive lifts, or lifts and interposed material, but it results in the final product presenting such definite and precise color effects as to give an undesirable barber pole effect. So far as I am aware no one heretofore has been able to make a heel using lifts of leatherboard or fiberboard, or other material, or synthetic product of generally uniform structure and obtain a pleasing variable color effect comparable to that obtainable by the use of leather lifts, and of the same general nature so that they are often indistinguishable from each other.

In accordance with the method of the present invention, however, such results are accomplished, as well as of hardening and strengthening the material, so that it is no longer friable and does not check or creep. The method may also be applied to good advantage in the making of heels with leather lifts since it prevents subsequent creeping and checking of the lifts in service, thus preserving the heel contour and while it may to some extent modify it does not injuriously affect the desired color variations in the finished heel surface.

Referring to the accompanying drawing, Figure 1 is a top plan in half-tone of a leatherboard heel lift as it appears after an intermediate step in the process of this invention.

Figure 2 is a side elevation in half-tone of a completed heel.

In order to carry out this invention the lifts are treated with a hardening agent which may comprise a pitchy or resinous material or a gum which may be dissolved in a suitable somewhat volatile solvent. Among the gums may be mentioned copal, dammar, mastic,elenia andsandarac. A satisfactory resin or pitchy material comprises rosin of which there are various grades, some more pitchy than others. These materials are cut by a solvent such as benzol, acetone or dibutyl alcohol. For example, 70 to 80 ounces of rosin may be dissolved in from a pint to a quart of such solvent. desired strength for saturating purposes and partly in order that the saturant may be used at a temperature higher than the boiling points of these solvents the diluting liquid may be one which is miscible with the solvents but which has a higher boiling point. For example, this This is then diluted to the' 0 merse the died out lifts.

may comprise a high boiling point naphtha or a petroleum oil such as kerosene or mixtures of the two. The solution may be thinned with this high boiling point liquid sufiiciently to produce, say, one gallon of saturant. Care must be taken not to add so much of the high boiling point liquid that the resins or gums tend to go out of solution and into suspension, but enough should be added so that the solution when placed in a hot water jacket may be raised to, say, 180 F. to 190 F. without causing rapid loss of the solvent. By this treatment the material may be handled in open kettles without undue loss of the solvents. The sheet material which is is desired to use is then dipped in the impregnating solution at a temperature of, say, 180 F. to 190 F., the material being, if desired, in relatively large sheets, although it is preferable in the case of heel manufacturing to im- This not only saves any saturating material which would otherwise be absorbed in that part of the sheet material which would appear as waste from the dieing out operations, but it also makes possible a more extensive range of color variations in the finished product between different portions of individual laminations or lifts. For example, this saturating may be done by placing the lifts or other out blanks in a metal basket and immersing them in the impregnating solution elevated above room temperature for, say, one to two minutes, the longer the immersion the darker the color within reasonable limits. A treatment at about 185 F. is quite satisfactory. If the temperature be much above 190 the heat is liable to damage the fibrous blanks.

The blanks may then be removed from the saturating tank and while they remain in the basket in more or less random registration with each other they are allowed to cool. Those portions which are less exposed to the air when removed from the tank are, when cool, lighter in color than those which are more exposed and the random registration of the blanks or lifts causes 45 some delay in access of air and cooling to those 55 of the material may be treated in the saturant and it will be found that there is still variation in coloring in the finished product, those portions adjacent to the edges of the sheet being different from those portions toward the interior, and the surface portions at the faces being somewhat differently shaded than those toward the interior of the sheet. Apparently the pitchy, resinous materials or gums, carried by the solvent into the blanks migrate toward the surface when the solvent escapes, so that those parts of the blanks adjacent to the more exposed surfaces ultimately contain more of these saturating materials than the portions less exposed and impart corresponding variations of their own distinctive colorations to various portions of the blanks. While these variations appear to some extent in the blanks or sheets after they have been cooled after the saturating treatment, they are much more marked in the finished product.

The blanks or lifts can then be assembled in any usual or suitable way into the desired articles, the blanks being stuck together, as by the use of ordinary glue or any other suitable adhesive, or paste, such as is commonly employed for the purpose, or, if desired, the article maybe built up with thin pyroxylin sheeting between the lifts, after which by immersion for a few seconds in any of the more rapid pyroxylin solvents such as a mixture of acetone and ethyl acetate the pyroxylin becomes adhesive and secures the laminations together firmly after they have been put in the press and left there under pressure for a few minutes. They then may be removed from the presses and thoroughly dried out, as, for example, being left until the next day. They then may be compressed and doweled or have other treatment accorded to them such as is usualv in making up the heel blanks or logs.

These heel blanks or logs are then trimmed to the desired shape and are scoured first with coarse sandpaper and then with fine sandpaper, then slicked with worn out sandpaper in accordance with the usual practice in making leather heels. Then an annaline dye cut with a solvent such as benzol, may, if desired, be applied either with a brush or by dipping, or if desired the dye may be incorporated in the original saturant. The heel may then be subjected to treatment with a rotary cotton roll applying tripoli, the friction acting to impart a slight shine to the surface and bringing out the color and color variations to a considerable extent at the surface of the heel where the edges of the laminations or lifts are exposed. A finishing wax such, for example, as carnauba wax may then be applied with a rotary leather covered roll, after which a rotary brush may be used to remove the excess wax and the final polish may be given on a rotary rag wheel, these finishing treatments of the heel being carried out in a manner similar to that commonly employed in connection with leather heels. Best results seem to be produced with leatherboard, inter-felted fibrous materials which do not contain leather being in general less satisfactory in the final ornamental appearance of the heels in regard to variations of color.

Where colors other than brown or black aredesired, it is preferable to employ light colored leatherboard and the lighter colored gums, as otherwise the colors may be deeply tinged with brown, but for browns and very dark colors the red or brown leatherboard and rosin are very satisfactory. The treatment by the saturant with the resultant uneven distribution of the residual materials acts correspondingly to prevent equal action of the dyes in coloring the lifts, the dyes acting selectively more on those portions of the lifts containing the lesser proportions than on those portions containing the greater proportions of such material.

Not only may sheet materials formed up from inter-felted fibrous material be treated in accordance with the method of this invention, but leather lifts themselves or entire heels whether composed of leather, leatherboard or fiberboardmay also be treated in the same way, the treatment acting to harden the lifts or articles to such an extent that they are not liable to creep or check and mar the surface appearance of the heels after some time of use. While the treatment of individual leather lifts may to some extent modify the natural color variation which might be produced by the use of leather lifts without the treatment, nevertheless the va-' 5. A heel comprising superposed lifts of sheeted riations are such in the final product that the effect is substantially undistinguishable from that produced by using leather lifts not subjected to the saturating treatment. Laminations of wood may also be treated in the same way, the laminations then being further variegated in color by the grain effects of the wood. It should, of course, be evident, as previously noted 'that other articles than heels 'maybe made up in accordance with this invention where similar hardening of the laminations is desired, together with similar variations in color and shade between adjacent lifts or laminations and in different portions of the same. Figure 2 of the drawing is a half-tone photographic enlarged reproduction of a heel made in accordance with this invention, the two lifts at the heel seat end and the three lifts nearest to the tread being made of leather and the intermediate lifts beingv made of leatherboard. Probably due to the fact that colors do not show, there is an appearance of rather more contrast between the leather and leatherboard lifts than in the actual article, and particularly in the darker color finishes it is often very difficult to distinguish between the leather and leatherboard lifts. It will be noted that there are presented on the surface of the heel striations of lighter and darker color variations irregularly disposed throughout the lengths of the striations and with reference to the faces of the lifts and varying at random in adjacent lifts or laminations. In many parts of the finished article it is exceedingly difficult to determine the exact locations of the edges of adjacent laminations.

From the foregoing description of the preferred method ofthis invention and a certain product produced by the practice of such methd, it should be evident to those skilled in the art that various changes and modifications might be made without departing from the spirit or scope of this invention as defined by the'appendq ed claims.

I claim:

1. A laminated article the laminations of which comprise sheeted fibrous material, the edges of said laminations being exposed at a surface of said article and presenting random striated color variations irregularly disposed throughout the lengths of the striations and with reference to the faces of the laminations.

2. A laminated article the laminations of which comprise sheeted fibrous material, the

edges of said laminations being exposed at a surface of said article and presenting random striated color variations irregularly disposed throughout the lengths of the striations and with reference to the faces of the laminations and varying at random in adjacent laminations.

3. A laminated article, the laminations of which comprise fibrous material and a harden-- ing saturating agent selected from a group comprising gums and resins, the edges of such laminations being exposed on a surface of said article and presenting random, striated color variations irregularly disposed throughout the lengths of the striations and with reference to the faces of the laminations.

4. An article comprising superposed laminations of fibrous material stiffened and colored by an impregnant containing rosin non-uniformly distributed and presenting random striated color variations irregularly disposed throughout the lengths of the striations and with reference to the faces of the laminations.

r a a l) fibrous material, the edges of such lifts defining a surface contour of such heel and presenting random striated color variations irregularly disposed throughout the lengths of the striations and with reference to the faces of the laminations.

, 6. A heel comprising superposed lifts each of adjacent lifts being of fibrous material saturated with rosin and presenting in the exposed edges of said lifts random striated color variations irregularly disposed throughout the lengths of the striations and with reference to the faces of the laminations.

lifts striations of darker and lighter color of in definite outlines and of widths generally less than the thickness of said lifts and irregularly disposed with relation to the faces of the lifts.

10. The method which comprises treating at an elevated temperature pieces of fibrous sheet material with a'solution of a hardening agent selected from a group comprising gums and resins, cooling the pieces at least somewhat unequally thus producing variations in color from said agent, assembling and securing said pieces into a laminated structure, and finishing the surface thereof presenting surfaces of said laminations to present variations in color between adjacent laminations and in different portions of the same lamination.

11. The method which comprises dissolving rosin in a volatile solvent, adding a high boiling naphtha to the solution to an amount to raise the boiling point of the solution to at least 180 F.

while maintaining the rosin in solution, dipping into said solution at an elevated temperature a mass comprising pieces of fibrous sheeted material in random contact with each other, removing said mass, securing said pieces together in face to face relation to form a laminated article, and finishing and polishing a face of said article comprising edge faces of said laminations.

12. The method which comprises dissolving an' laminations resulting from-the previoustreat' ment. I

13. The method which comprises dissolving an agent selected from a group comprising gums and resins, in a volatile solvent, increasing the boiling point of the solution to at least approximately 190 F. by'the addition of a" high boiling point liquid miscible therewith, dipping into said solution while heated from about 180 F. to 190- said lifts random striated F. a mass comprising pieces of fibrous material insheeted form and in random contact with each other, removing said mass and permitting it to cool, building up a laminated article from such pieces with a face comprising cut sections of the other, removing said mass and permitting it tocool, building up a laminated article from such pieces with a face comprising cut sections of the laminations, applying a dye to said face and then polishing said face. I

15. The method which comprises dissolving an agent selected from a group comprising gums and resins in a volatile solvent, increasing the boiling point of the solution to at least approximately 190 F. by the addition of a high boiling point liquid miscible therewith, dipping into said solution while heated from about F. to F. a mass comprising pieces of fibrous material in sheeted form and in random contact with each other, removing said mass and permitting it to cool, building up a laminated article from such pieces with a face comprising cut sections of the laminations, applying a dye to said face and then waxing and polishing said face.

16. The method which comprises treating at an elevated temperature pieces of fibrous sheet material with a solution of a hardening agent selected from a group comprising gums and resins together with a dye, cooling the pieces at least somewhat unequally thus producing variations in color from said agent, assembling and securing said pieces into a laminated structure, and finishing the surface thereof presenting surfaces of said laminations to present variations in color between adjacent laminations and in different portions of the same lamination.

17. "The method which comprises saturating pieces of fibrous sheet material with a solution of a hardening agent and drying such pieces under conditions to produce non-uniform distribution of the agent therethrough, forming a laminated article from said pieces with a face presenting edges thereof, treating said face with a dye selectively acting on the less completely saturated portions to thereby present non-uniform color effects, and finishing and polishing said face.

JOSEPH F. POLLARD. 

